Study done in post-menopausal women to determine whether prolonged dietary KHCO3 supplementation increases serum growth hormone concentrations. Serum GH concentrations will be measured during normal nocturnal sleep, and in response to standard GH secretory stimuli (infusion of growth hormone na darginine), pre- and during KHCO3 supplementation. These assessments will be made on two-day admissions per subject, separated by an interval of 4 weeks, for a total of 15 subjects. The study will utilize the GCRC over a period of 2 years.